title: Simultaneous compared with sequential blood pressure measurement results in smaller inter-arm blood pressure differences.
abstract: There are currently few recommendations on how to assess inter-arm blood pressure (BP) differences. The authors compared simultaneous with sequential measurement on mean BP, inter-arm BP differences, and within-visit reproducibility in 240 patients stratified according to age (<50 or ≥60 years) and BP (<140/90 mm Hg or ≥140/90 mm Hg). Three simultaneous and three sequential BP measurements were taken in each patient. Starting measurement type and starting arm for sequential measurements were randomized. Mean BP and inter-arm BP differences of the first pair and reproducibility of inter-arm BP differences of the first and second pair were compared between both methods. Mean systolic BP was 1.3±7.5 mm Hg lower during sequential compared with simultaneous measurement (P<.01). However, the first sequential measurement was on average higher than the second, suggesting an order effect. Absolute systolic inter-arm BP differences were smaller on simultaneous (6.2±6.7/3.3±3.5 mm Hg) compared with sequential BP measurement (7.8±7.3/4.6±5.6 mm Hg, P<.01 for both). Within-visit reproducibility was identical (both r=0.60). Simultaneous measurement of BP at both arms reduces order effects and results in smaller inter-arm BP differences, thereby potentially reducing unnecessary referral and diagnostic procedures.
authors.affiliation: Departments of Internal and Vascular Medicine, Academic Medical Center of the University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Niels V
authors.initials: NV
authors.lastname: van der Hoeven
authors.forename: Sophie
authors.initials: S
authors.lastname: Lodestijn
authors.forename: Stephanie
authors.initials: S
authors.lastname: Nanninga
authors.forename: Gert A
authors.initials: GA
authors.lastname: van Montfrans
authors.forename: Bert-Jan H
authors.initials: BJ
authors.lastname: van den Born
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001132:Arm / Q000098:blood supply; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009819:Office Visits; D015203:Reproducibility of Results; D013997:Time Factors